Biochemical characterization of the self-sacrificing p-aminobenzoate synthase from Nitrosomonas europaea reveals key residues involved in selecting a Fe/Fe or Mn/Fe cofactor.

ABSTRACT: A noncanonical route for p-aminobenzoate (pABA) biosynthesis in select bacteria utilizes a novel self-sacrificing heme oxygenase-like domain-containing oxidase/oxygenase (HDO) superfamily member. The recently characterized self-sacrificing pABA synthase from Chlamydia trachomatis ("CADD") requires manganese and likely employs a heterobimetallic Mn/Fe cofactor. A conserved active site tyrosine residue is cleaved from the protein backbone to serve as the substrate for pABA synthesis and a lysine residue is the amino group donor. Here, we investigated the orthologous pABA synthase from the ammonia-oxidizing bacterium, Nitrosomonas europaea, which we refer to as NePabS. Consistent with the previously studied C. trachomatis enzyme, purified NePabS produces pABA in vitro in a reaction that only

SUBMITTER: Stone S 

PROVIDER: S-EPMC11965152 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature